Section 250.518 - Tubing and wellhead equipment(a) No tubing string may be placed in service or continue to be used unless such tubing string has the necessary strength and pressure integrity and is otherwise suitable for its intended use. (1) The tubing string must be evaluated for burst, collapse, and axial loads with appropriate safety factors and material design factors for the pressure and temperature environments of the completion, production, shut-in, and injection load cases.(2) The tubing string materials must be appropriate for the environment. You must follow NACE Standard MR0175-2003 (incorporated by reference in § 250.198 ) when H2 S concentration may equal or exceed 0.05 psi partial pressure.(3) The tubing string threaded connectors must be appropriate for the loads identified in paragraph (a)(1) of this section.(b) When the tree is installed, you must equip wells to monitor for casing pressure according to the following chart: | If you . . . | you must equip . . . | so you can monitor . . . |
| (1) fixed platform wells, | the wellhead, | all annuli (A, B, C, D, etc., annuli). |
| (2) subsea wells, | the tubing head, | the production casing annulus (A annulus). |
| (3) hybrid * wells, | the surface wellhead, | all annuli at the surface (A and B riser annuli). If the production casing below the mudline and the production casing riser above the mudline are pressure isolated from each other, provisions must be made to monitor the production casing below the mudline for casing pressure. |
* Characterized as a well drilled with a subsea wellhead and completed with a surface casing head, a surface tubing head, a surface tubing hanger, and a surface christmas tree.
(c) You must design and test the wellhead, tree, and related equipment in accordance with ANSI/API Spec. 6A (incorporated by reference in § 250.198 ) or ANSI/API Spec. 17D (incorporated by reference in § 250.198 ), as applicable. The wellhead, tree, and related equipment must have a pressure rating greater than the maximum anticipated surface pressure and must be designed, installed, operated, maintained, and tested to achieve and maintain pressure containment and pressure control.(1) Newly completed dry trees (e.g., fixed, hybrid, or mudline suspension) for production or injection wells must be equipped with a minimum of one master valve and one surface safety valve (SSV), installed above the master valve, in the vertical run of the tree.(2) Newly completed subsea production or injection wells must be equipped with a minimum of one USV installed in the horizontal or vertical run of the tree (e.g., vertical or horizontal subsea trees).(3) Newly completed wells with a mudline suspension conversion to a subsea tree must have a minimum of two casing strings tied back and sealed below the tubing head. At a minimum, the production casing and the next outer casing must be tied back to the wellhead, to ensure annular isolation.(d) You must install, maintain, and test surface and subsurface safety equipment in accordance with the applicable requirements in subpart H of this part.(e) When installed, packers and bridge plugs must meet the following:(1) The uppermost permanently installed packer and all permanently installed bridge plugs qualified as mechanical barriers must comply with ANSI/API Spec. 11D1 (as incorporated by reference in § 250.198 );(2) The production packer must be set at a depth that will allow for a column of weighted fluids to be placed above the packer that will exert a hydrostatic force greater than or equal to the force created by the reservoir pressure below the packer;(3) The production packer must be set as close as practically possible to the perforated interval; and(4) The production packer must be set at a depth that is within the cemented interval of the selected casing section.(f) Your APM must include a description and calculations for how you determined the production packer setting depth.(g) You must have two independent barriers, one being mechanical, in the exposed center wellbore prior to removing the tree and/or well control equipment. 76 FR 64462 , Oct. 18, 2011. Redesignated at 77 FR 50894 , Aug. 22, 2012, as amended at 81 FR 26021 , Apr. 29, 2016; 81 FR 61918 , Sept. 7, 2016; 84 FR 21976 , May 15, 2019 81 FR 26021 , 4/29/2016; 84 FR 21976 , 7/15/2019; 89 FR 71120 , 10/29/2024